Mental hospital shooting suspect told ex-roommate to 'get out' before opening fire, injuring 3

At least three people are injured after a man on the fifth floor of a mental institution brandished a gun and a knife.

It happened around 3:20 p.m. Friday at the Turtle Creek Valley Mental Health hospital near Pittsburgh, WPXI-TV reported.

The unidentified suspect reportedly told his former roommate, who was also on the fifth floor, to "get out of here. I'm not going to hurt you." The suspect's former roommate then went downstairs and called 911 as the suspect allegedly stabbed another person.

One woman told WPXI-TV that she heard as many as three gunshots. Another woman standing outside the building said her niece, who works at the hospital, sent her a text saying the suspect was holding her hostage inside.

Dozens of police units and a SWAT team was dispatched to the site. The building was later evacuated and at least two nearby schools were put on lockdown, according to WTAE-TV.

CJ Fulton, who works at the hospital, said the suspect "was angry from something that happened" while he was a patient at the facility.

"[W]hen he was staying there with us, when he was a patient, and he started saying, 'You ruined my life,' and he proceeded to stab individuals and assault individuals inside the office and other staff members on the unit," Fulton told WTAE-TV.